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The rapid development of miniaturization and refinement of modern electronic components has led to higher requirements for nanosized powders. The barium strontium titanate (Ba1-xSrxTiO3, BST) nanopowders with fine grains, uniform particle size and high purity have broad application prospects. Herein, BST nanopowders were synthesized via nonhydrolytic sol-gel method and the effects of different processing parameters on structure were investigated systematically by using X-ray diffraction, transmission electron microscopy, laser particle size analyser and thermogravimetric mass spectrometry. In the first step, different dispersants, dispersant concentration and calcination temperature were selected for synthesis of Ba0.6Sr0.4TiO3 powder to find optimal conditions. In the second step, these optimal conditions were used to synthesize BST powders, but different (Ba+Sr)/Ti and Ba/Sr molar ratios were used to find those that can enable preparation of single phase cubic perovskite powder. Therefore, this study showed how the processing parameters can be systematically tuned with the idea to obtain ultra-fine single phase BST nanoparticles.

Novel tungstate SrLa6-xW10O40: xEu3+ (x = 0, 0.03, 0.06, 0.09, 0.12, 0.15, 0.18, 0.21) red phosphors were prepared by solid state method at 1150 °C by using SrCO3, La2O3, WO3 and Eu2O3 as raw materials. The powders were agglomerated with particles having mostly spheroidal morphology, mean particle size D50 = 12.8 μm and narrow particle size distribution. With the increase of doping amount x, there is no significant difference in the diffraction peak position of the phosphor, but the cell volume of SrLa6W10O40 slowly decreases. The relative strength of diffraction peaks decreases gradually and the half-peak width widens gradually, indicating that the inclusion of Eu3+ ions affects the crystallization of the SrLa6W10O40 matrix. Excitation and emission spectra of the prepared samples were obtained. The optimal doping content has the SrLa5.85W10O4: 0.15Eu3+ phosphor and is characterised with the colour coordinate of (0.652, 0.348), which is closer to the red standard colour (0.67, 0.33) than the near-ultraviolet red phosphor Y2O2S: Eu3+ (0.622, 0.351) used for commercial LED.